It is not today that we are curious to find other worlds, in 1610, Europa a moon of the planet Jupiter was discovered by Galileo Galilei with a small telescope. Slightly smaller than the moon, Europa has an ice crust on its surface and a possibly iron-nickel core and surrounded by rocks, it is the ideal place to sustain life off the earth. Europa has the smoothest surface of any solid object in the Solar System, which would make it easier for some spacecraft to land on this moon. Without a doubt, we all know that water is very important to sustain life as we know it, and Europa offers much of that benefit. Europa has a large ocean below its surface, which would be an exemplary habitat for life, bearing organic compounds, heat (from tidal force) and possibly hydrothermal vents, which could contain beings similar to what we see on Earth, as annelids, molluscs and arthropods.

In 2012, the Hubble Space Telescope acquired an image that was interpreted as a water vapor plume erupting from a cryogeniser near the southern pole of Europa, the image suggests that the cloud could reach 200 kilometers in height, which is very good because it has more habitat types for life generation. With images of the Hubble Space Telescope we can observe a small ionosphere and different from the oxygen of the Earth's atmosphere, that of Europa is not biologically formed, it is probably generated by the dissociation of water vapor that splits into hydrogen and oxygen, where hydrogen escapes from the atmosphere by having a very low atomic mass, leaving only the oxygen in the atmosphere.

Several researches have been done on bacteria that would possibly survive conditions similar to the moon Europa, an example is a data analysis done by researchers from the University of São Paulo (USP) about a bacterium that lives in a mine of oura in Mponeng, Africa This bacterium survives without sunlight at a depth of 2.8 kilometers. In the bowels of the mine it contains water leaks through cracks in the rocks that have radioactive uranium, uranium breaks down the water particles producing free radicals that attack the rocks at sulfate, the bacterium uses sulfate to synthesize a nucleotide responsible for storing energy in the cells. This environment is similar to the ocean floor of Europa.

Even with our understanding of life formation, it is a mystery how life has formed on Earth. We all know that it probably all started with extremophile organisms in the depths of our ancient ocean. And Europa is certainly the cosmic body most like Earth millions of years ago. By having an environment with multiple habitats, Europa has a great potential for the origin of life. A major concern with the ocean of Europa would be the gateway to the discovery of extraterrestrial life, and even the origin of life on Earth.